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Technician support for operation and maintenance of large fusion experiments: the tandem mirror experiment upgrade (TMX-U) approach (open access)

Technician support for operation and maintenance of large fusion experiments: the tandem mirror experiment upgrade (TMX-U) approach

As experiments continue to grow in size and complexity, a few technicians will no longer be able to maintain and operate the complete experiment. Specialization is becoming the norm. Subsystems are becoming very large and complex, requiring a great deal of experience and training for technicians to become qualified maintenance/operation personnel. Formal in-house and off-site programs supplement on-the-job training to fulfill the qualification criteria. This paper presents the Tandem Mirror Experiment-Upgrade (TMX-U) approach to manpower staffing, some problems encountered, possible improvements, and safety considerations for the successful operation of a large experimental facility.
Date: December 1, 1983
Creator: Mattson, G.E.
System: The UNT Digital Library
Review of recent measurements of charmed particle lifetimes using emulsions (open access)

Review of recent measurements of charmed particle lifetimes using emulsions

This talk is a review of results which have been reported during the past year on charmed particle decays in emulsions.
Date: December 1, 1979
Creator: Voyvodic, L.
System: The UNT Digital Library
Computer program SCAP-BR for gamma-ray streaming through multi-legged ducts (open access)

Computer program SCAP-BR for gamma-ray streaming through multi-legged ducts

A computer program, SCAP-BR, has been developed at Burns and Roe for the gamma-ray streaming analysis through multi-legged ducts. SCAP-BR is a modified version of the single scattering code, SCAP, incorporating capabilities of handling multiple scattering and volumetric source geometries. It utilizes the point kernel integration method to calculate both the line-of-sight and scattered gamma dose rates by employing the ray tracing technique through complex shield geometries. The multiple scattering is handled by a repeated process of the single scatter method through each successive scatter region and collapsed pseudo source meshes constructed on the relative coordinate systems. The SCAP-BR results have been compared with experimental data for a Z-type (three-legged) concrete duct with a Co-60 source placed at the duct entrance point. The SCAP-BR dose rate predictions along the duct axis demonstrate an excellent agreement with the measured values.
Date: December 8, 1977
Creator: Byoun, T. Y.; Babel, P. J. & Dajani, A. T.
System: The UNT Digital Library
Catalytic steam gasification of bagasse for the production of methanol (open access)

Catalytic steam gasification of bagasse for the production of methanol

Pacific Northwest Laboratory (PNL) tested the catalytic gasification of bagasse for the production of methanol synthesis gas. The process uses steam, indirect heat, and a catalyst to produce synthesis gas in one step in fluidized bed gasifier. Both laboratory and process development scale (nominal 1 ton/day) gasifiers were used to test two different catalyst systems: (1) supported nickel catalysts and (2) alkali carbonates doped on the bagasse. This paper presents the results of laboratory and process development unit gasification tests and includes an economic evaluation of the process. 20 references, 6 figures, 9 tables.
Date: December 1, 1983
Creator: Baker, E.G. & Brown, M.D.
System: The UNT Digital Library
Transverse spin observables in chromodynamics (open access)

Transverse spin observables in chromodynamics

Quantum Chromodynamics confronts a harsh series of tests in the attempt to formulate a comprehensive approach to the calculation of transverse spin observables. The basic obstacles to understanding transverse spin can be illustrated by considering the transverse structure function g{sub T}(x, Q{sup 2}) = g{sub 1}(x, Q{sup 2}) + g{sub 2}(x, Q{sup 2}), extracted from deep-inelastic scattering using a polarized lepton and a polarized proton. The inadequacy of the transverse-spin basis for quarks and gluons found there suggests a new approach to the problems of single-spin observables in large-transverse-momentum processes. This approach, presented earlier for single spin production asymmetries, is discussed here. It is shown that the mechanism can also lead to baryon polarization effects at large P{sub T}. 14 refs.
Date: December 1, 1989
Creator: Sivers, D.
System: The UNT Digital Library
Effects of energy constraints on transportation systems. [Twenty-six papers] (open access)

Effects of energy constraints on transportation systems. [Twenty-six papers]

Twenty-six papers are presented on a variety of topics including: energy and transportaton facts and figures; long-range planning under energy constraints; technology assessment of alternative fuels; energy efficiency of intercity passenger and freight movement; energy efficiency of intracity passenger movement; federal role; electrification of railroads; energy impact of the electric car in an urban enviroment; research needs and projects in progress--federal viewpoint; research needs in transportation energy conservation--data needs; and energy intensity of various transportation modes--an overview. A separate abstract was prepared for each of the papers for inclusion in Energy Research Abstracts (ERA) and in Energy Abstracts for Policy Analysis (EAPA).
Date: December 1, 1977
Creator: Mittal, R. K.
System: The UNT Digital Library
Performance of a coincidence based blood activity monitor (open access)

Performance of a coincidence based blood activity monitor

A new device has been constructed that measures the positron emitting radio-tracer concentration in arterial blood by extracting blood with a peristaltic pump, then measuring the activity concentration by detecting coincident pairs of 511 keV photons with a pair of heavy inorganic scintillators attached to photomultiplier tubes. The sensitivity of this device is experimentally determined to be 610 counts/second per {mu}Ci/ml, and has a paralyzing dead time of 1.2 {mu}s, so is capable of measuring blood activity concentration as high as 1 mCi/ml. Its performance is compared to two other blood monitoring methods: discrete blood samples counted with a well counter and device that uses a plastic scintillator to directly detect positrons. The positron detection efficiency of this device for {sup 18}F is greater than the plastic scintillation counter, and also eliminates the radioisotope dependent correction factors necessary to convert count rate to absolute concentration. Coincident photon detection also has the potential of reducing the background compared to direct positron detection, thereby increasing the minimum detectable isotope concentration. 10 refs., 6 figs.
Date: December 1, 1989
Creator: Moses, W. W.
System: The UNT Digital Library
Formation of H/sup -/ by charge transfer in alkaline-earth vapors (open access)

Formation of H/sup -/ by charge transfer in alkaline-earth vapors

Progress since the last symposium on the study of H/sup -/ formation by charge transfer in alkaline-earth vapors is reported. High yields are obtained at low energies, in agreement with theoretical predictions.
Date: December 5, 1983
Creator: Schlachter, A.S. & Morgan, T.J.
System: The UNT Digital Library
Proceedings of the Fifth Annual Participants' Information Meeting: DOE Low-Level Waste Management Program (open access)

Proceedings of the Fifth Annual Participants' Information Meeting: DOE Low-Level Waste Management Program

The meeting consisted of the following six sessions: (1) plenary session I; (2) disposal technology; (3) characteristics and treatment of low-level waste; (4) environmental aspects and performance prediction; (5) overall summary sessions; and (6) plenary session II. Fifty two papers of the papers presented were processed for inclusion in the Energy Data Base. (ATT)
Date: December 1, 1983
Creator: unknown
System: The UNT Digital Library
Quarks and gluons in hadrons and nuclei (open access)

Quarks and gluons in hadrons and nuclei

These lectures discuss the particle-nuclear interface -- a general introduction to the ideas and application of colored quarks in nuclear physics, color, the Pauli principle, and spin flavor correlations -- this lecture shows how the magnetic moments of hadrons relate to the underlying color degree of freedom, and the proton's spin -- a quark model perspective. This lecture reviews recent excitement which has led some to claim that in deep inelastic polarized lepton scattering very little of the spin of a polarized proton is due to its quarks. This lecture discusses the distribution functions of quarks and gluons in nucleons and nuclei, and how knowledge of these is necessary before some quark-gluon plasma searches can be analyzed. 56 refs., 2 figs.
Date: December 1, 1989
Creator: Close, F. E.
System: The UNT Digital Library
Measurement of B sup 0 -- B sup 0 Mixing Using the MARK II at PEP (open access)

Measurement of B sup 0 -- B sup 0 Mixing Using the MARK II at PEP

B{sup 0}{bar B}{sup 0} mixing has been observed now by several experiments. The signature is the observation of an excess of same-sign dilepton events in datasets containing semileptonic B decays. Several years ago the MARK II published an upper limit on B{sup 0}{bar B}{sup 0} mixing at E{sub cm} = 29 GeV, using data taken at the e{sup +}e{sup {minus}} storage ring PEP. Here we report on the results of a new analysis with increased statistics, using refined methods with better sensitivity and control of systematic effects. 10 refs., 2 figs., 2 tab.
Date: December 1, 1989
Creator: Porter, F.
System: The UNT Digital Library
Universal formula for the quasistatic second-order density perturbation by a cold magnetoplasma wave (open access)

Universal formula for the quasistatic second-order density perturbation by a cold magnetoplasma wave

Using the general expression for the ponderomotive Hamiltonian, the quasi-static quasi-neutral density change caused by the ponderomotive force of a cold magnetoplasma wave of arbitrary frequency and polarization is obtained. This formula agrees with and extends previous results for unmagnetized and magnetized plasma.
Date: December 16, 1977
Creator: Kaufman, A. N.; Cary, J. R. & Pereira, N. R.
System: The UNT Digital Library
International conference on bone mineral measurement, October 12--13, 1973, Chicago, Illinois (open access)

International conference on bone mineral measurement, October 12--13, 1973, Chicago, Illinois

From international conference on bone mineral measurement; Chicago, Illinois, USA (12 Oct 1973). Abstracts of papers presented at the international conference on bone mineral measurement are presented. The papers were grouped into two sessions: a physical session including papers on measuring techniques, errors, interpretation and correlations, dual photon techniques, and data handling and exchange; a biomedical session including papers on bone disease, osteoporosis, normative data, non-disease influences, renal, and activity and inactivity. (ERB)
Date: December 31, 1973
Creator: unknown
System: The UNT Digital Library
Tracking with wire chambers at high luminosities (open access)

Tracking with wire chambers at high luminosities

Radiation damage and rate limitations impose severe constraints on wire chambers at the SSC. Possible conceptual designs for wire chamber tracking systems that satisfy these constraints are discussed. Computer simulation studies of tracking in such systems are presented. Simulations of events from interesting physics at the SSC, including hits from minimum bias background events, are examined. Results of some preliminary pattern recognition studies are given. 11 refs., 10 figs.
Date: December 1, 1989
Creator: Hanson, G. G.
System: The UNT Digital Library
Ion cyclotron radio frequency systems and performance on the tandem mirror experiment-upgrade (TMX-U) (open access)

Ion cyclotron radio frequency systems and performance on the tandem mirror experiment-upgrade (TMX-U)

High power ion cyclotron radio frequency (ICRF) systems are now gaining greater attention than before as prime driver ion heating systems. Lawrence Livermore National Laboratory (LLNL) has installed a 200 kW high frequency (HF) transmitter system on its Tandem Mirror Experiment-Upgrade (TMX-U). This paper describes the system, antenna, controls, and monitoring apparatus. The transmitter operates into a high Q antenna installed in the central cell region of the experiment. It incorporates a dual-port feedback system to automatically adjust the transmitter's output power and allow the maximum consistent with the plasma loading of the antenna. Special techniques have been used to measure, in real-time, the dynamically changing loading values presented by the plasma. From the measurements, the antenna impedance can be optimized for specified plasma density.
Date: December 1, 1983
Creator: Moore, T. L.; Molvik, A. W.; Cummins, W. F.; Pedrotti, L. R.; Henderson, A. L.; Karsner, P. G. et al.
System: The UNT Digital Library
Evaluating late detection capability against diverse insider adversaries (open access)

Evaluating late detection capability against diverse insider adversaries

This paper describes a model for evaluating the late (after-the-fact) detection capability of material control and accountability (MCandA) systems against insider theft or diversion of special nuclear material. Potential insider cover-up strategies to defeat activities providing detection (e.g., inventories) are addressed by the model in a tractable manner. For each potential adversary and detection activity, two probabilities are assessed and used to fit the model. The model then computes the probability of detection for activities occurring periodically over time. The model provides insight into MCandA effectiveness and helps identify areas for safeguards improvement. 4 refs., 4 tabs.
Date: December 3, 1987
Creator: Sicherman, A.
System: The UNT Digital Library
Heavy ion drivers for inertial confinement fusion (open access)

Heavy ion drivers for inertial confinement fusion

The advantages of heavy ion beams as a way of delivering the needed energy and power to an inertial fusion target are surveyed. The existing broad technology base of particle accelerators provides an important foundation for designing, costing, and evaluating proposed systems. The sequence of steps needed for the verification of the heavy ion approach is described; recent research results are even more encouraging than had been assumed hitherto.
Date: December 1, 1983
Creator: Keefe, D.
System: The UNT Digital Library
Portable software for distributed readout controllers and event builders in FASTBUS and VME (open access)

Portable software for distributed readout controllers and event builders in FASTBUS and VME

We report on software developed as part of the PAN-DA system to support the functions of front end readout controllers and event builders in multiprocessor, multilevel, distributed data acquisition systems. For the next generation data acquisition system we have undertaken to design and implement software tools that are easily transportable to new modules. The first implementation of this software is for Motorola 68K series processor boards in FASTBUS and VME and will be used in the Fermilab accelerator run at the beginning of 1990. We use a Real Time Kernel Operating System. The software provides general connectivity tools for control, diagnosis and monitoring. 17 refs., 7 figs.
Date: December 1, 1989
Creator: Pordes, R.; Berg, D.; Berman, E.; Bernett, M.; Brown, D.; Constanta-Fanourakis, P. et al.
System: The UNT Digital Library
Modified Murnaghan equation of state applied to shock compression of silica, basalt, and dolomite (open access)

Modified Murnaghan equation of state applied to shock compression of silica, basalt, and dolomite

An equation of state previously used by the author is developed further and applied to geologic media. The equation is of the same form as the Murnaghan equation of state, but with the elastic constant terms replaced by the cohesive energy density (internal pressure), and the exponential term given as a sum of the Gruneisen parameter and the gaseous adiabatic exponent. Data for shock compression of silica, basalt, and dolomite are analyzed according to the equation.
Date: December 20, 1965
Creator: Rogers, L.A.
System: The UNT Digital Library
Heavy leptons at the SSC (open access)

Heavy leptons at the SSC

It is argued that detection of heavy leptons at the Superconducting Super Collider seems to be very difficult but perhaps not impossible. The feasibility is shown to depend critically upon the ability to identify events with W's decaying hadronically and missing transverse momentum. (LEW)
Date: December 15, 1987
Creator: Anderson, G. & Hinchliffe, I.
System: The UNT Digital Library
The Mark II Silicon Strip Vertex Detector and performance of a silicon detector telescope in the Mark II detector at the SLC (open access)

The Mark II Silicon Strip Vertex Detector and performance of a silicon detector telescope in the Mark II detector at the SLC

A Silicon Strip Vertex Detector (SSVD) consisting of 36 independent silicon detector modules has been built for use in the Mark II detector at the SLAC Linear Collider (SLC). We discuss the performance of the individual modules and the stability and accuracy of their placement in the mechanical support. To gain operational experience at the SLC, we have assembled and placed inside the Mark II a telescope made of three Silicon Detector Modules. We present results from the first data run of the SLC on the overall performance of the Telescope, including backgrounds, charged particle tracking and spatial resolution. 7 refs., 10 figs.
Date: December 1, 1989
Creator: Labarga, L.; Adolphsen, C.; Gratta, G.; Litke, A.; Turala, M.; Zaccardelli, C. (California Univ., Santa Cruz, CA (USA). Inst. for Particle Physics) et al.
System: The UNT Digital Library
B physics theory (open access)

B physics theory

The status of the theoretical predictions for loop decays, strategy for precise determination of Vub and the issue of symmetric versus asymmetric machine for a B factory were discussed in the working group. While from our present perspective observation of CP violation appears as the most prominent goal for a B factory, the importance and richness of other B physics was stressed. 23 refs.
Date: December 1, 1989
Creator: Soni, A. (Brookhaven National Lab., Upton, NY (USA). Physics Dept.)
System: The UNT Digital Library
Small Angle Physics at CDF: A Progress Report (open access)

Small Angle Physics at CDF: A Progress Report

In 1989 CDF collected data in special high beta runs with a trigger selecting elastic and inelastic events in order to measure the total cross section ({sigma}{sub tot}) and the differential elastic cross section (d{sigma}{sub el}/dt). Data were taken at cms energies of 300, 540, 1000 and 1800 GeV. A double arm magnetic spectrometer located along the beam pipe tags the particles scattered at very small angles and tracking detectors surrounding the interaction point reveal particles produced at larger angles. We discuss the status of the analysis of elastic and inelastic events with emphasis on the event selection and the background subtraction. 5 refs., 14 figs., 3 tabs.
Date: December 16, 1989
Creator: Paoletti, Riccardo
System: The UNT Digital Library
Properties of leptons (open access)

Properties of leptons

The properties of the electron, muon, tau, and their neutrinos are reviewed. Three discrepancies in our understanding of those properties are discussed: the lifetime of orthopositronium, the mass spectra of e{sup +}e{sup -} pairs produced in heavy ion collisions, and the 1-charged particle modes problem in tau decays. The review concludes with a discussion of what we need to learn about the tau and the consequent need for a tau-charm factory. 68 refs., 7 figs., 8 tabs.
Date: December 1, 1989
Creator: Perl, Martin L.
System: The UNT Digital Library